This invention relates to the addition of blends of magnesium oxide and copperoxychloride to inhibit the deposition of calcium oxide deposit in coal-fired lime kilns.
The use of copperoxychloride to inhibit deposit formation is disclosed in Kiss, L. T., et al., "The Use of Copperoxychloride to Alleviate Boiler Slagging", Journal of the Institute of Fuel, April 1972, pages 213 through 223.
U.S. Pat. No. 2,845,338 discloses the use of blends of magnesium oxide and copperoxychloride to inhibit deposit in coal-fired boiler furnaces. The percent of calcium oxide deposit in these furnaces is generally less than ten percent. The principal deposits are SiO.sub.2, Al.sub.2 O.sub.3, and Fe.sub.2 O.sub.3.
Formation of heavy calcium oxide deposits on the walls of coal-fired lime kilns is known as "coal ring". The "ring" reduces the effective diameter of the kiln, increasing the pressure drop across its length.
Since the secondary air for combustion is provided by fans, any increase in pressure drop adversely affects the firing rate and hence the kiln's productivity. Generally the buildup is removed by shooting the deposit with industrial size shot gun shells, known as "shoot out".
The process of the instant invention does not eliminate the "shoot out" requirements, but does significantly reduce the frequency for "shoot out".